EP-4737760-A1 - FLOATING-TYPE BASE ISOLATION SYSTEM

Abstract

Provided is a floating seismic isolation system (100), including: a storage space (116) in which a liquid for allowing a floating structure (120) to float in the liquid is stored; a first chamber (132), inside which a compressible fluid is accommodated, and which has a volume that is variable according to a pressure fluctuation of the liquid; and a second chamber (134), inside which the compressible fluid is accommodated, and which has a pressure or a volume that passively changes according to a volume change of the first chamber (132).

Inventors

• SHIMADA, TAKAHIRO
• MOTEGI, HARUKI
• OTANI, AKIHITO

Assignees

• IHI Corporation

Dates

Publication Date

20260506

Application Date

20241118

Claims (9)

1. A floating seismic isolation system, comprising: a storage space in which a liquid for allowing a floating structure to float in the liquid is stored; a first chamber, inside which a compressible fluid is accommodated, and which has a volume that is variable according to a pressure fluctuation of the liquid; and a second chamber, inside which the compressible fluid is accommodated, and which has a pressure or a volume that passively changes according to a volume change of the first chamber.
2. The floating seismic isolation system according to claim 1, further comprising a throttle flow path that allows the first chamber and the second chamber to be in communication with each other.
3. The floating seismic isolation system according to claim 1 or 2, wherein a wall surface having rigidity is interposed between the compressible fluid in the second chamber and the liquid.
4. The floating seismic isolation system according to claim 1 or 2, wherein the first chamber includes an elastic membrane that is allowed to be in contact with the liquid.
5. The floating seismic isolation system according to claim 1 or 2, wherein the first chamber includes: a cylinder; and a piston, which has a top surface that is allowed to be in contact with the liquid, and which is slidably provided in the cylinder.
6. The floating seismic isolation system according to claim 2, further comprising a wall surface that defines the storage space, wherein the throttle flow path is formed at the wall surface.
7. The floating seismic isolation system according to claim 2, wherein the first chamber includes a plurality of sub-chambers, wherein volumes of the plurality of sub-chambers of the first chamber are individually variable according to the pressure fluctuation of the liquid, and wherein the throttle flow path comprises a plurality of throttle flow paths extending from the plurality of sub-chambers of the first chamber, respectively.
8. The floating seismic isolation system according to claim 7, wherein the second chamber includes a plurality of sub-chambers, and wherein the plurality of sub-chambers of the second chamber are in communication with at least one of the plurality of throttle flow paths.
9. The floating seismic isolation system according to claim 1 or 2, further comprising a third chamber that is in communication with the second chamber, and is provided on the ground.

Description

Technical Field The present disclosure relates to a floating seismic isolation system. This application claims the benefit of priority to Japanese Patent Application No. 2023-207130 filed on December 7, 2023, and contents thereof are incorporated in this application. Background Hitherto, a floating seismic isolation system using a liquid has been developed. As the floating seismic isolation system, for example, in Patent Literature 1, there is disclosed a technology in which a liquid is accommodated in a recess formed in a ground, and a floating structure is caused to float in the liquid. In the technology of Patent Literature 1, a plurality of air chambers are provided at a bottom of the floating structure, and the air chambers function as a damper that absorbs vertical shaking during an earthquake. Citation List Patent Literature Patent Literature 1: JP 2004-1667 A Summary Technical Problem However, in Patent Literature 1 above, there is disclosed no mechanism for reducing shaking during an earthquake in a portion other than the floating structure, and hence there is room for further reducing shaking during an earthquake. In view of such a problem, the present disclosure has an object to provide a floating seismic isolation system that enables reducing shaking during an earthquake by a seismic isolation structure provided in a space accommodating a liquid. Solution to Problem In order to solve the above-mentioned problem, according to one aspect of the present disclosure, there is provided a floating seismic isolation system, including: a storage space in which a liquid for allowing a floating structure to float in the liquid is stored; a first chamber, inside which a compressible fluid is accommodated, and which has a volume that is variable according to a pressure fluctuation of the liquid; and a second chamber, inside which the compressible fluid is accommodated, and which has a pressure or a volume that passively changes according to a volume change of the first chamber. Moreover, the above-mentioned floating seismic isolation system may include a throttle flow path that allows the first chamber and the second chamber to be in communication with each other. Moreover, a wall surface having rigidity may be interposed between the compressible fluid in the second chamber and the liquid. Moreover, the first chamber may include an elastic membrane that is allowed to be in contact with the liquid. Moreover, the first chamber may include: a cylinder; and a piston, which has a top surface that is allowed to be in contact with the liquid, and which is slidably provided in the cylinder. Moreover, the above-mentioned floating seismic isolation system may include a wall surface that defines the storage space, and the throttle flow path may be formed at the wall surface. Moreover, the first chamber may include a plurality of sub-chambers, volumes of the plurality of sub-chambers of the first chamber may be individually variable according to the pressure fluctuation of the liquid, and the throttle flow path may include a plurality of throttle flow paths extending from the plurality of sub-chambers of the first chamber, respectively. Moreover, the second chamber may include a plurality of sub-chambers, and the plurality of sub-chambers of the second chamber may be in communication with at least one of the plurality of throttle flow paths. Moreover, the above-mentioned floating seismic isolation system may further include a third chamber that is in communication with the second chamber, and is provided on the ground. Advantageous Effects of Invention According to the present disclosure, it is possible to reduce shaking during an earthquake by the seismic isolation structure provided in the space accommodating the liquid. Brief Description of Drawings FIG. 1 is an explanatory view for illustrating a floating seismic isolation system according to an embodiment of the present disclosure.FIG. 2 is an explanatory view for illustrating a seismic isolation structure in the embodiment.FIG. 3 is an explanatory view for illustrating a seismic isolation structure in a first modification example.FIG. 4 is an explanatory view for illustrating a seismic isolation structure in a second modification example.FIG. 5 is an explanatory view for illustrating a seismic isolation structure in a third modification example. Description of Embodiments Now, with reference to the attached drawings, embodiments of the present disclosure are described in detail. The dimensions, materials, and other specific numerical values represented in the embodiments are merely examples used for facilitating the understanding of the disclosure, and do not limit the present disclosure unless otherwise particularly noted. Elements having substantially the same functions and configurations herein and in the drawings are denoted by the same reference symbols to omit redundant description thereof. Further, illustration of elements with no direct relationship to the